Rapid Communication: The loss of residual visual memories over the passage of time

Abstract

There has been extensive discussion of the causes of short-term forgetting. Some accounts suggest that time plays an important role in the loss of representations, whereas other models reject this notion and explain all forgetting through interference processes. The present experiment used the recent-probes task to investigate whether residual visual information is lost over the passage of time. On each trial, three unusual target objects were displayed and followed by a probe stimulus. The task was to determine whether the probe matched any of the targets, and the next trial commenced after an intertrial interval lasting 300 ms, 3.3 s, or 8.3 s. Of critical interest were recent negative (RN) trials, on which the probe matched a target from the previous trial. These were contrasted against nonrecent negative (NRN) trials, in which the probe had not been seen in the recent past. RN trials damaged performance and slowed reaction times in comparison to NRN trials, highlighting interference. However, this interfering effect diminished as the intertrial interval was lengthened, suggesting that residual visual information is lost as time passes. This finding is difficult to reconcile with interference-based models and suggests that time plays some role in forgetting.

The visual nonverbal memory trace is fragile when actively maintained, but endures passively for tens of seconds

“…Response times to RP stimuli were also slowed in Experiment 1, though generally the PI effect was confined to accuracy. Our demonstration of PI is compatible with previous studies (e.g., Cyr et al, 2017;Hartshorne, 2008;Makovski & Jiang, 2008;McKeown et al, 2014;Mercer & Duffy, 2015) and highlights its role in short-term forgetting. More significantly, the PI effect was largely robust over time, as assessed through an interaction between probe type and ITI length.…”

“…Experiment 3 (and the subsequent two experiments) also increased the sample size, to improve statistical power and increase the likelihood of detecting a reduction in PI. A previous study detecting a reduction in PI over time (Mercer & Duffy, 2015) employed a sample of 29 individuals, and effort was made to obtain a similar sample size in the final three experiments.…”

Control of information in working memory: Encoding and removal of distractors in the complex-span paradigm

“…First, there is strong evidence that at least verbal contents of working memory do not decay (Lewandowsky et al, 2009;Oberauer & Lewandowsky, 2013, 2014. Second, findings that are often cited in support of decay for non-verbal materials -a modest decline of accuracy over several seconds -imply a decay rate much too slow for clearing out working memory at the pace at which our stream of consciousness progresses (McKeown & Mercer, 2012;Mercer & Duffy, 2015;Mercer & McKeown, 2014;Ricker & Cowan, 2010;Ricker, Spiegel, & Cowan, 2014;Zhang & Luck, 2009). Working memory could not function as well as it does without removing outdated information, and the present experiments confirm a role for removal of distractors in keeping working memory working.…”

Time manages interference in visual short-term memory

“…Indeed recently, there has been a growing consensus that both decay and interference play a role in forgetting, with slow time-based decay processes acting as a form of 'eraser' for redundant memory content (Altmann & Gray, 2002;Altmann & Schunn, 2012). Decay of the trace since encoding in this view is an adaptive process which removes residual representations, and by doing so reduces proactive interference (Hardt, Nader & Nadel, 2013;Mercer & Duffy, 2015). Decay also plays an important role in an influential current model of attention-based memory, the time-based resource sharing model (TBRS; Barrouillet, Bernardin, & Camos, 2004;Barrouillet, Bernardin, Portrat, Vergauwe, & Camos, 2007;Vergauwe, Dewaele, Langerock, & Barrouillet, 2012;Vergauwe, Hartstra, Barrouillet, & Brass, 2015).…”